Multi-layer circuit boards operatively receive electronic components and allow the received components to be desirably interconnected to selectively and cooperatively form electrical circuits. Particularly, these components are operatively received upon opposed board surfaces and within certain interior portions of the board, thereby desirably allowing each of the electronic circuit boards to contain a relatively large amount of components which efficiently, respectively, and densely populate the respective boards.
It is desirable to allow each of the component containing surfaces or portions of a created and/or formed electronic circuit board to communicate and/or to be selectively interconnected, thereby allowing the contained electronic components to cooperatively and selectively form a relatively large number of desired electrical circuits. This desired communication and/or interconnection typically requires the use of shared electrical ground planes, the transmittal of electrical power and/or control type signals between some or all of the component containing surfaces or board portions, and/or the connection of components on each of the opposed surfaces and/or within and between certain of the interior portions and the top and/or bottom and/or other board surfaces.
This desired interconnection typically requires that one or more holes be formed or drilled through each of the circuit boards, thereby creating at least one “through hole” or “via” traversing between each of the opposed component containing surfaces and through the various interior circuit board portions. Typically this drilling process is relatively complex and time consuming, thereby increasing the overall circuit board production cost. This drilling process also undesirably damages and/or destroys many of the circuit boards, thereby further increasing overall production cost.
Further, it is desirable to form “air-bridges” or “crossover type circuits” upon one or more selected surfaces and/or within certain component containing portions of the formed circuit board in order to allow multiple levels of circuits and/or electrical interconnections to be formed upon a single board surface and/or within a certain component containing portion of the circuit board, thereby desirably increasing the amount of electrical circuits which may be created upon and/or within the created circuit board (e.g., increasing the density of the contained electrical circuitry).
These “air bridges” or crossover circuits are typically formed by rather complicated, costly, and time consuming processes. The formed bridges and crossover circuits further do not typically and efficiently accommodate certain desirable circuit board interconnection processes, techniques, and/or methodologies, such as and without limitation, the use of relatively heavy wire bonding (e.g., aluminum wire having a diameter of about five to about twenty milli-meters) or the direct connection of components to a surface of the board.
There is therefore a need to provide an electronic circuit board and a method for producing a multi-layer electronic circuit board which overcomes some or all of the previously delineated drawbacks of prior electronic circuit boards and methods for making a circuit board, which selectively allows grounded and non-ground “vias” to be desirably and selectively and efficiently formed in a cost effective manner, and which further allows for the efficient and selective formation of air-bridge members or crossover circuits which desirably accommodate diverse types of circuit interconnection processes and which increase the circuitry density within the formed electronic circuit board.